Caspar Einem is the son of composer Gottfried von Einem and his wife Lianne, née von Bismarck. After studying jurisprudence in Vienna, gaining the degree of Dr. jur. in 1971, Einem worked as a probation officer in Vienna and Salzburg. After this, he worked for the Austrian Chamber of Workers. In 1991, he became a manager for the OMV, Austria's biggest gas and oil company, where he eventually was director of the Department for Gas. Currently, he is Vice-President of the European Forum Alpbach.
He is married and has a son.
In 1994, Einem became Secretary of State, which boosted his career. From 1995 until 1997 he was Interior Minister of Austria, and later, until 2000, Minister for Science and Traffic. In his time as Interior Minister, it was his task to clear up the series of briefcase bomb attacks that haunted Austria in those years.
Since the election victory of ÖVP and FPÖ in 2000, he has been a member of the National Council of Austria. He was elected in the Central-Western-District of Vienna (Alsergrund, where he has also been Chairman of the local SPÖ organisation until 2008. Einem was deputy chairman of his party's parliamentary group, spokesman for European Affairs and a highly influential figure in his party. He is considered a liberal leftist and a staunch anti-fascist, always rejecting any kind of collaboration with FPÖ or BZÖ. He served as President of the Social Democratic University Alumni Association, as well as of one of the European social partner CEEP and its Austrian section VÖWG. On October 12 Einem publicly announced to become one of the board members of the chartered airplane provider Jetalliance and to withdraw from politics.